This invention relates generally to illumination devices for wristwatches, and more particularly to an exterior illumination device carried by the watchband.
Various types of illumination devices have been proposed for wristwatches to enable reading the time under poor light conditions. Such devices usually take the form of small incandescent bulbs powered by a battery and arranged inside the case of the wristwatch, assisted by light pipes or reflectors to enable the numerals on the dial be seen. It has been proposed to carry the small button cell or battery outside the watchcase in a special attachment connected to the watchband as shown, for example, in U.S. Pat. No. 3,018,614 issued Jan. 30, 1962 and U.S. Pat. No. 3,224,184 issued Dec. 21, 1965, both in the name of A. Brien. The Brien patents show the incandescent bulb carried in the watch crystal, connected to the battery by lead-in wires, and operated by a switch. U.S. Pat. No. 3,025,662 issued Mar. 20, 1962 to Fleishman et al discloses a hinged cover containing an incandescent lamp for illuminating the dial, having a switch making contact with a power source carried on the watch strap when the hinged cover is opened.
U.S. Pat. No. 3,729,923 issued May 1, 1973 to Brigliano et al discloses an incandescent bulb carried on the watchcase and connected to a battery in an attachment connected between the watchband and the case by means of lead wires. A deformable or flexible wall allows the circuit to be closed to illuminate the dial by pressing the flexible wall.
The foregoing arrangements, because of lead wires passing between the power source in the watchband attachment and the incandescent bulb in the case or crystal are subject to possible malfunction, due to breakage of the wires caused by repetitive movement between the case and the attachment. Also, the arrangements shown are not easily removable or detached from the wristwatch, and thereby preclude the user from having the option of either utilizing the illumination device or removing it.
Accordingly, one object of the present invention is to provide a completely self-contained illumination device which is used, or not, at the wearer's option.
Another object of the invention is to provide improved illumination device with no lead wires passing between moving parts of the watch.